EM client crashing repeatedly

1

This is a recent issue, where clicking on certain emails would crash it. I would delete them to avoid it. However its the top email currently from my daughters oncologist requesting a video appt. ever ytime it restarts, it crashes. I use a VPN and always have upto date kasperky’s security on. This has been going on for a week.. maybe 2 but intermittent until now.

here is the first part of the error message.


eM Client
10.3.2619.0

false

Microsoft Windows NT 10.0.26100.0
8.0.18
en-US
en-US


System.ArgumentException
An item with the same key has already been added. Key: Title:Video Consult with Dr. Dan Rubin, Start:09/25/2025 14:00:00, Local:09/25/2025 16:00:00, TZ:(UTC-07:00) Arizona End:09/25/2025 14:45:00, Local:09/25/2025 16:45:00, TZ:(UTC-07:00) Arizona
System.Private.CoreLib



System.Private.CoreLib.dll
100672064
System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e
System.ThrowHelper
ThrowAddingDuplicateWithKeyArgumentException


System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e





System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e

key



0
1b




System.Private.CoreLib.dll
100697317
System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e
System.Collections.Generic.Dictionary2</type> <name>TryInsert</name> <parameters> <parameter> <assembly>System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e</assembly> <type /> <name>key</name> </parameter> <parameter> <assembly>System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e</assembly> <type /> <name>value</name> </parameter> <parameter> <assembly>System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e</assembly> <type>System.Collections.Generic.InsertionBehavior</type> <name>behavior</name> </parameter> </parameters> </method> <offset>0</offset> <nativeoffset>263</nativeoffset> <filename /> </frame> <frame> <method> <modulename>MailClient.Abstractions.dll</modulename> <metadatatoken>100663736</metadatatoken> <assembly>MailClient.Abstractions, Version=10.3.0.0, Culture=neutral, PublicKeyToken=null</assembly> <type>MailClient.Utils.CalendarUtils</type> <name>GetEventRelativePositions</name> <parameters> <parameter> <assembly>System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e</assembly> <type>System.Collections.Generic.Dictionary2[[MailClient.Schedule.Event.IEvent, MailClient.Schedule, Version=10.3.0.0, Culture=neutral, PublicKeyToken=null],[MailClient.Utils.CalendarUtils+EventSizeAndLocation, MailClient.Abstractions, Version=10.3.0.0, Culture=neutral, PublicKeyToken=null]]
eventsSizesAndLocations


System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e
System.Collections.Generic.IEnumerable1[[MailClient.Schedule.Event.IEvent, MailClient.Schedule, Version=10.3.0.0, Culture=neutral, PublicKeyToken=null]]</type> <name>EventsToShow</name> </parameter> <parameter> <assembly>System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e</assembly> <type>System.Collections.Generic.List1[[System.DateTime, System.Private.CoreLib, Version=8.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]]
internalVisibleDays


System.Private.CoreLib, Version=8.0.0.0, Culture=neutral,

2

Ok I was able to click in a different email real fast to keep it from crashing, but these are emails from multiple sources every few days that I will click on and get kicked out. I was able to right click it and forward, but if I left click I crash.

3

This is a recent issue, where clicking on certain emails would crash it. I would delete them to avoid it. However its the top email currently from my daughters oncologist requesting a video appt. ever ytime it restarts, it crashes.

Could possibly be a eg: corrupt senders email depending on if any other emails do it as well. Does it happen with any other different emails?

I use a VPN and always have up to date kasperky’s security on.

Also could be possibly one of those programs causing it like the kasperky security program eg: intercepting it when you click on it.

Try “disabling those completely” and then close and reopen eM Client & see if the problem still happens.

If eM Client then works ok, then “enable them one at a time” to find out which one it is.

Apart from that there is references in that message to do with an eg: public key tokens, so could be related net frameworks in your OS or encryption in some way.

4

no, numerous senders emails. I tried disconnecting everything and clicked on one of the emails and same thing. I noted a duplicate key error but don’t know what that is. I don’t use encrypted emails on this account.

5

Ok as disabling the Security program and VPN made no difference and you use no encryption, then check your “Netframeworks are up to date” via the Windows updates.

If Windows is all up to date , suggest next to try uninstalling eM Client and “don’t delete the database” when asked on the uninstall wizard and then reinstall V10.3.2619 via the release history page and see if that fixes it.

Next If uninstalling and reinstalling makes no difference try running a database repair as per @Gary post in the following thread.

Note:- Before running the repair, make a manual backup via “Menu / Backup” incase you need to restore for any reason. You can see when the backup is complete in Show Operations via clicking the drop-down on the right of Refresh.

If then running the repair makes no difference then suggest next if you have a paid active Pro, Personal or Business version, go to the VIP support page and login and lodge a support ticket.

6

ok is there a unistall wizard or just use windows uninstall?? I have that version, but I will try to reinstall first.

7

Yes just go to the usual windows uninstall area which will automatically being up the eM Client uninstall wizard as part of it and it will ask you part way through if you want to delete the database so choose “don’t delete on that”. Then reinstall.

Try running the database repair first though I just “added to my post above” before uninstalling and reinstalling. That might fix it without uninstalling and reinstalling as might be a corruption in your database “as it’s affecting more than one email”.

.

8

Ok reinstalled, and repaired. Same issue.

9

Ok reinstalled, and repaired. Same issue

The next step is to lodge a support ticket.